<!DOCTYPE html>
<html lang="en">
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>waves</title>
  <link rel="stylesheet" href="./style.css" type="text/css" />
  <body>
    <div class="frame"></div>
    <script>
      const frame = document.querySelector(".frame");
      const frag = document.createDocumentFragment;
      for (let i = 0; i < 20; i++) {
        const div = document.createElement("div");
        div.classList.add("row");
        for (let j = 0; j < 20; j++) {
          const cell = document.createElement("div");
          cell.classList.add("circle");
          div.appendChild(cell);
        }
        frame.appendChild(div);
      }
      frame.style.setProperty("--row", 20);
      frame.appendChild(frag);
    </script>
  </body>
</html>
